How Small Is Big Enough?

Andrew,
Thanks for your interesting reply.
Please permit me to offer some more commentary.
> Andrew Case wrote: Right. I thought about this as an even simpler approach. The problem
I see is that the energy may be deposited mostly in the outer layers
of the NEA, where it does the least good.
This still does not seem to require rendezvous, in fact it still tends to favor an impact mission. A penetrator/impactor can penetrate deeper into the body than a soft lander, without the need to drills or complex equipment..

> > The other variant involves hitting a nickel-iron NEA with an impactor
> > that releases CO, forming carbonyls which can again be studied
>
> Where does the CO come from ? Does the probe carry it along ? What
> causes the release ?
The CO is carried on the impactor, and released by a mechanism triggered
by the impact. This sort of device is well understood, having been used Ah, interesting. This could be worth proposing as a low-cost NASA mission.